As a conventional inkjet recording method, a piezo method for jetting an ink droplet by changing a shape of an ink passage according to vibration of a piezoelectric element, and a thermal method for making a heat generator provided in an ink passage heat to generate air bubbles and jetting an ink droplet according to a pressure change by the air bubbles in the ink passage are known, however, recently, an electrostatic sucking method for charging ink in an ink passage to jet an ink droplet by a electrostatic sucking force of the ink such as one described in JP-Tokukaihei-11-277747 or JP-Tokukai-2000-127410 has been increasing.
However, the above-mentioned inkjet recording method has the following problems.
(1) Limit and Stability of a Minute Liquid Droplet Formation
Since a nozzle diameter is large, a shape of a droplet jetted from a nozzle is not stabilized, and there is a limit of making a droplet minute.
(2) High Applying Voltage
For jetting a minute droplet, miniaturization of a jet opening of the nozzle is an important factor. In a principle of the conventional electrostatic sucking method, since the nozzle diameter is large, electric field intensity of a nozzle edge portion is weak, and therefore, in order to obtain necessary electric field intensity for jetting a droplet, it is necessary to apply a high jetting voltage (for example, extremely high voltage near 2000[V]). Accordingly, in order to apply a high voltage, a driving control of a voltage becomes expensive.
Thereupon, to provide a liquid jetting apparatus capable of jetting a minute droplet is a first object. At the same time, to provide a liquid jetting apparatus capable of jetting a stable droplet is a second object. Further, to provide a liquid jetting apparatus in which it is possible to jet a minute droplet and landing accuracy is high is a third object. Further, to provide a liquid jetting apparatus which can reduce an applying voltage and is cheap is a fourth object.